Abstract

Thin vacuum deposited films of aluminum tris(8-hydroxyquinolinate) embedded in matrix at concentrations corresponding to a single-molecule distribution are investigated. The spectral properties of the films are studied by luminescence spectroscopy. It is established that the dilution of in the matrix leads to blueshift of the luminescence maximum up to compared to pure layers. In contrast to the recently reported facial isomer of in the crystalline phase, we conclude from our spectral data the observation of facial isomer molecules.